Grinding or buffing machine



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H. STEVENS GRINDING 0R BUFFING MACHINE Filed Aug. 6, 1927 INVENTOR. WQRHEEB-TEV A TTORNE Y.

sag, 233(1), 393 H. D. STEVENS 39737941? I GRINDING OR BUFFING MACHINE Filed Aug. s, 1927 s Sheeis-Shsei 2 3Q, 19., H. D. sTEvENs GRINDING OR BUFFING MACHINE Filed Aug. 6,, 1927 3 sheets sheet 3 INVENTOR. HDRAEE1 EITEVEN5 BY 6% A TTORNE Y Patented Deal 30, 1930 UITED STATES I PATENT OFFICE HORACE D. STEVENS, F AKRON, OHIO, ASSIGNOR TO THE FIRESTONE TIRE AND RUBBER COMPANY, OF AKRON, OHIO, A CORPORATION OF OHIO GRINDING OR BUFFING MACHINE Application filed August 6, 1927. Serial No. 211,203.

I This invention relates to grinding or buffing machines and has particular reference to semi-automatic machines for grinding, butting or polishing casters, rollers, rings or other annular or disc-shaped objects.

The object of the invention isto devise semi-automatic means for accurately, speedily and safely grinding or polishing annular or disc-like objects. A further object is to devise a machine comprising a traveling, abrasive belt, rotating bufling wheel, or the like, means for conveying and successively presenting annular objects to the belt or wheel to be buffed or ground, and means for removing the finished objects from the conveying means.

The foregoing and other objects are obtained by the device illustrated in the accompanyingdrawings and described below. It is to be un erstood that the invention is not limited to he specific embodiment thereof disclosed herein.

Of the accompanying drawings,

Figure 1 is a plan view of a machine embodying theprinciples of the invention; Figure 2 isa rear elevation thereof; Figure 3 is a plan detail of a portion of the machine as viewed from below;

Figure 4 is a side elevation of the machine as viewedfrom the discharge side thereof;

Figure 5 is asvertical section taken on the line 5+5 of Figure 1; and t Figure 6 is a vertical section taken on the line 6-6 of Figure 1.

Referring to the drawings, 10 represents standards for supporting a table 11 carrying units under surface the driving mechanism of the device as shown in Figure 3. Power is derived froma motor 12 mounted on bracket 13 attached to the table, the shaft. 14 of the motor having fixed thereto a pinion 15 meshing with a gear 16 to rotate shaft 17.

A small sprocket 18 drives chain 19 which is trained over a large sprocket 2O fixed to shaft 2O journaled through the table, and

pinion 21, turning with sprocket 20, meshes.

with gear 22 to rotate shaft 23 and the arm 24 attached to the upper end thereof at a reduced rate of speed. Y

On top of table 11, arm 24 carries on one end an upwardly projecting roller 25 to engage a star cam 26 for intermittently rotating carriage wheel or turret 27 through a portion of a revolution, star cam 26 and wheel 27 being integrally formed and journaled about 55 hearing 27 through which shaft 20 passes. Pivoted arms 28 mounted on wheel 27 each have a stud 29 on one end for holding the articles to be ground or buffed, while each of the other ends of the arms is yicldingly held 0 I against a stop pin 30 by a spring 31 connected to arm 32, the latter being attached to shaft 33 which is journaled through wheel 27 and fixed in its respective arm 28. Reverse motion of wheel 27 is prevented by the action of leaf spring pawl 34 which engages behind ratchet teeth 35 on wheel 27 and forward rotary motion of the latter is arrested by a brake 36 yieldingly' pressed against the outer periphery of the wheel when the end of arm 24 op- 7 posite roller 25 engages leaf spring 37 just as said rolleris disengaged from the star cam, this position of arm 24 and leaf spring 37 being shown by dotted lines in Figure 1. Brake 36 and leaf spring 37 are connected to a sleeve 38 pivoted on a stud shaft 39 adjustably mounted on table ,11. Spring-pressed roller 40 snaps successively into recesses 41 to stop wheel 27 at the correct operating position. lhe abrasive or bufiing means illustrated .in the drawings by a dotted line comprises a grinding or polishing belt 42 trained over pulleys 43 and 44. Pulley 43 is attached to shaft 17 which is journaled in bearing 45 and is driven by gear 16 as previously noted. Pulley 44 is pivoted on lever arm 46mountcd to swlng on stud shaft 47 so that belt 42 may be held under tension by a spring 48 stretched between lever arm 46 and a stud 49 mounted so in table 11. In order to resist pressure of the annular object 50 to be ground or polished, a spring-pressed roller 51 engages the back of the belt at the point of contact, maintaining a uniform pressure of the belt against the object. The opposite side of the object 50 is contracted by a drive wheel 52 for rotating the object in a direction counter to the direction of belt 42. Drive wheel 52 is journaled on a stud shaft 53 carried by a bracket 54-100 which in turn clamped to the upper end of bearing 27. A. gear 55 fixed on theupper end of shaft 20 meshes with a gear 56 fixed to drive wheel 52 for rotating the latter in the end of stud shaft 53,-whereby arm 59 may be adjusted to tilt roller 57 ata slight Vertical angle for raising object off stud 29 when roller 58 is rotated. A belt 61 trained over pulleys 62 and 63 attachedto shafts 17 and 58, respectively, serves to rotate the take-oft roller, and the latter with help of a guard 64 discharges the finished objects into a chute 65. A reamer or drill 66 may be mounted on the machine and driven from the drive thereof for cleaning or boring central apertures of the objects to be ground so that they will fit over studs 29.

In the operation of the machine. for grinding or bufling mold marks ofi' rubber casters. for instance, the operator reams a central aperture in the casters and places one on each stud carried by the intermittently rotated carriage wheel. The drive wheel 52 successively engages each caster, forcing it radially outwardly against the traveling abrasive belt .for a shortperiod of time and rotating the caster in a direction opposite to that of the belt. As the finished caster passes on, it is engaged by the take-off roller which removes the caster from the stud and discharges it into the outlet chute. I

The operation'of the machine is thus entirely automatic with the exception of the stop of placing the objeetsonto studs 29, and grinding or bufling is accurately and rapidly accomplished thereby with safety for-the operator.

'Modifications of the construction herein disclosed maybe resorted to without departurefrom the. scope of the invention as defined by the appended claims. What is claimed is 1. A grinding or bnfling machine comprising a conveyor wheel, studs carriedby said conveyor wheel and adapted to have freely ournalled thereon objects to be ground or hailed. a traveling abrasive element, means for intermittently rotating said conveyor wheel to bring each object successively into engagement with said abrasive element, and means for rotating said objects on said studs I, in a direction counter to the direction of the abrasive element.

2. In a machine of the class described, a turretfor conveying articles to be ground or bufi'ed, means carried by said turret upon .which said articles may be mounted and which are pivoted for movement transversely of the path of travel of said turret, a travel ing abrasive element, and means for successivel forcing the articles transversely of their path of travel to cause the periphery of said articles to come into engagement with 

